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991.
H.C. Arredondo ValdezG. García Jiménez S. Gutiérrez GranadosC. Ponce de León 《Chemosphere》2012,89(10):1195-1201
The degradation of paracetamol in aqueous solutions in the presence of hydrogen peroxide was carried out by photochemistry, electrolysis and photoelectrolysis using modified 100 pores per inch reticulated vitreous carbon electrodes. The electrodes were coated with catalysts such as TiO2 and CuO/TiO2/Al2O3 by electrophoresis followed by heat treatment. The results of the electrolysis with bare reticulated vitreous carbon electrodes show that 90% paracetamol degradation occurs in 4 h at 1.3 V vs. SCE, forming intermediates such as benzoquinone and carboxylic acids followed by their complete mineralisation. When the electrolysis was carried out with the modified electrodes such as TiO2/RVC, 90% degradation was achieved in 2 h while with CuO/TiO2/Al2O3/RVC, 98% degradation took only 1 h. The degradation was also carried out in the presence of UV reaching 95% degradation with TiO2/RVC/UV and 99% with CuO/TiO2/Al2O3/RVC/UV in 1 h. The reactions were followed by spectroscopy UV-Vis, HPLC and total organic carbon analysis. These studies show that the degradation of paracetamol follows a pseudo-first order reaction kinetics. 相似文献
992.
The formation was investigated for different groups of disinfection byproducts (DBPs) during chlorination of filter particles from swimming pools at different pH-values and the toxicity was estimated. Specifically, the formation of the DBP group trihalomethanes (THMs), which is regulated in many countries, and the non-regulated haloacetic acids (HAAs) and haloacetonitriles (HANs) were investigated at 6.0≤pH≤8.0, under controlled chlorination conditions. The investigated particles were collected from a hot tub with a drum micro filter. In two series of experiments with either constant initial active or initial free chlorine concentrations the particles were chlorinated at different pH-values in the relevant range for swimming pools. THM and HAA formations were reduced by decreasing pH while HAN formation increased with decreasing pH. Based on the organic content the relative DBP formation from the particles was higher than previously reported for body fluid analogue and filling water. The genotoxicity and cytotoxicity estimated from formation of DBPs from the treated particle suspension increased with decreasing pH. Among the quantified DBP groups the HANs were responsible for the majority of the toxicity from the measured DBPs. 相似文献
993.
Pelfrêne A Waterlot C Mazzuca M Nisse C Cuny D Richard A Denys S Heyman C Roussel H Bidar G Douay F 《Environmental pollution (Barking, Essex : 1987)》2012,160(1):130-138
An investigation was undertaken to identify the most significant soil parameters that can be used to predict Cd, Pb, and Zn bioaccessibility in smelter-contaminated agricultural soils. A robust model was established from an extended database of soils by using: (i) a training set of 280 samples to select the main soil parameters, to define the best population to be taken into account for the model elaboration, and to construct multivariate regression models, and (ii) a test set of 110 samples to validate the ability of the regression models. Total carbonate, organic matter, sand, P(2)O(5), free Fe-Mn oxide, and pseudototal Al and trace element (TE) contents appeared as the main variables governing TE bioaccessibility. The statistical modeling approach was reasonably successful, indicating that the main soil factors influencing the bioaccessibility of TEs were taken into account and the predictions could be applicable for further risk evaluation in the studied area. 相似文献
994.
Balkıs N Aksu A Erşan MS 《Environmental science and pollution research international》2012,19(2):592-599
Introduction
In this study, total petroleum hydrocarbon (TPH) contents and some aliphatic and aromatic hydrocarbon concentrations were analysed in coastal sediments of hot points collected from along the Southern Black Sea Shelf. 相似文献995.
Basso A Attademo AM Lajmanovich RC Peltzer PM Junges C Cabagna MC Fiorenza GS Sanchez-Hernandez JC 《Environmental science and pollution research international》2012,19(1):214-225
Purpose
In this study, we determined normal serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) activities in Tupinambis merianae in order to obtain reference values for organophosphorus pesticide monitoring. 相似文献996.
Rosenbom AE Therrien R Refsgaard JC Jensen KH Ernstsen V Klint KE 《Journal of contaminant hydrology》2009,104(1-4):137-152
This study numerically investigates the influence of initial water content and rain intensities on the preferential migration of two fluorescent tracers, Acid Yellow 7 (AY7) and Sulforhodamine B (SB), through variably-saturated fractured clayey till. The simulations are based on the numerical model HydroGeoSphere, which solves 3D variably-saturated flow and solute transport in discretely-fractured porous media. Using detailed knowledge of the matrix, fracture, and biopore properties, the numerical model is calibrated and validated against experimental high-resolution tracer images/data collected under dry and wet soil conditions and for three different rain events. The model could reproduce reasonably well the observed preferential migration of AY7 and SB through the fractured till, although it did not capture the exact depth of migration and the negligible impact of the dead-end biopores in a near-saturated matrix. A sensitivity analysis suggests fast flow mechanisms and dynamic surface coating in the biopores, and the presence of a plough pan in the till. 相似文献
997.
Heinz Rüdel Winfried Schröder Karl Theo von der Trenck Gerhard Andreas Wiesmüller 《Environmental science and pollution research international》2009,16(5):486-498
Background Due to the requirements of the EU Water Framework Directive and other legal regulations (e.g., national laws like the German
Federal Soil Protection Act), but also due to the implementation of the new EU chemicals management system REACH, environmental
monitoring will gain increasing importance for the surveillance of environmental quality as well as for the assessment of
chemicals. Against this background, the Work Group on ‘Environmental Monitoring’ of the Division of ‘Environmental Chemistry
and Ecotoxicology’ within the German Chemical Society has compiled a position paper on substance-related environmental monitoring.
Scope Core elements of this position paper are the definitions of important terms like monitoring, exposure monitoring, effect monitoring,
and integrated monitoring. Moreover, temporal and spatial aspects (monitoring of spatial distributions, trend monitoring,
and retrospective monitoring) and their applications are discussed. The main focus of this position paper is the coverage
of aspects which have to be observed for the preparation and implementation of a monitoring program. Essential is the clear
specification of the targets of the monitoring which determine the development of the monitoring concept and its realization,
e.g., if environmental media (compartments) or organisms are most appropriate as samples for the aim of the study. Of course,
also the properties of the target substances are important (e.g., lipophilicity/bioaccumulation as pre-requisite for an exposure
monitoring with organisms). Finally, the monitoring phases of sample planning, sampling, storage and transport of samples,
selection of analytical methods, quality assurance measures as well as reporting are discussed.
Perspectives An important issue for the future is to link the quantification of chemicals in environmental compartments (exposure and pollution
monitoring) more closely to the study of biological effects (effect monitoring) than has been the case up to now. Furthermore,
by inclusion of a spatial differentiation, a comprehensive evaluation of the state of an ecosystem can be obtained and the
relevance of the results improved. Practical examples of monitoring studies which illustrate various aspects covered in this
position paper will be presented in a series of publications by members of the Work Group in the following issues of this
journal.
相似文献
Gerhard Andreas WiesmüllerEmail: |
998.
J.P. Bitog I.-B. Lee M.-H. Shin S.-W. Hong H.-S. Hwang I.-H. Seo J.-I. Yoo K.-S. Kwon Y.-H. Kim J.-W. Han 《Atmospheric environment (Oxford, England : 1994)》2009,43(30):4612-4621
This paper discusses about the quantitative effect of windbreak fences on wind velocity in the reclaimed land at Saemangeum in South Korea. Windbreak fences were constructed in the reclaimed land to reduce the wind velocity to prevent the generation and diffusion of dust. However, up to this time, no in-depth studies were conducted to quantitatively measure the effect of the windbreak fences on wind velocity thus an optimum windbreak structure is not yet determined. Using CFD simulations, the effects of fence porosity, fence height, and the distance between the adjacent fences were investigated. A wind tunnel experiment was initially conducted and data gathered were used to develop the CFD models. From the experiments and CFD simulations, the overall percentage difference of the measured velocities was 7.20% which is generally acceptable to establishing the reliability of the CFD models. The reduction effect on wind velocity was measured in between the adjacent fences up to a height of 0.6 m from the ground surface. In terms of porosity ( = 0, 0.2, 0.4, 0.6), 0.2 was found to be the optimum value. Conversely, the effect of fence height (0.6, 0.8 and 1.0 m) showed no significant difference; therefore, 0.6 m height is recommended. In addition, the reduction effect of distance between the adjacent fences (2, 4 and 6 m) on wind velocity having a 0.2 porosity has decreased to about 75% regardless of the distance. In the case of the reclaimed land in Saemangeum, a decrease of 75% can prevent the generation and diffusion of dusts. However, the source of dusts is very large. Therefore, constructing an array of windbreak with 6 m distance between them is deemed necessary. 相似文献
999.
Blood serum concentrations of perfluorinated compounds in men from Greenlandic Inuit and European populations 总被引:3,自引:0,他引:3
Lindh CH Rylander L Toft G Axmon A Rignell-Hydbom A Giwercman A Pedersen HS Góalczyk K Ludwicki JK Zvyezday V Vermeulen R Lenters V Heederik D Bonde JP Jönsson BA 《Chemosphere》2012,88(11):1269-1275
Perfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are used in large quantities. They are persistent and found in measurable levels in human serum around the world. They have been associated with developmental, hepatic, and carcinogenic effects in animal studies. The aim of the present study was to describe levels of PFCs in serum among Inuits from Greenland and inhabitants from Warsaw, Poland and Kharkiv, Ukraine. Furthermore, the aim was to define social- and lifestyle related determinants of exposure for these compounds. Serum levels of seven PFCs were analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS). The concentrations of PFOS and PFOA were the highest of all PFCs in all three populations with a total amount of almost 90% of the PFCs. The mean levels of PFOS and PFOA were in the Greenlandic Inuits 52 and 4.8 ng mL(-1), in Poland 19 and 5.2 ng mL(-1), and in Ukraine 8.1 and 1.9 ng mL(-1), respectively. Thus, levels of PFCs in the serum of Inuits on Greenland were among the highest described in a general population whereas the levels in Poland were similar to other industrialized countries. The exposure in Ukraine was rather low. In the Greenlandic Inuit population, intake of seafood, tea, age and area of living were significant determinants of PFOS concentrations and explained about 22% of the variation. For the other populations no strong determinants were found. 相似文献
1000.
Paisio CE Talano MA González PS Busto VD Talou JR Agostini E 《Environmental science and pollution research international》2012,19(8):3430-3439